Beat yolks until foamy... gradually add 3/4 cup sugar; beat until thickened. In a large bowl, beat egg whites until soft peaks form. Fold egg yolk mixture into egg whites. Stir in cream and remaining 3/4 cup sugar. Transfer into a three quart saucepan and cook over medium heat, stirring occasionally until mixture coats a spoon. Do not boil! Add vanilla, chill thoroughly. Freeze.
